report generation does not honor event order

[mathisdt]

The report generation mechanism seems to have problems with the order in which events are interpreted if at any time a week's sum is negative.

Also see #21.

[mathisdt]

java.lang.RuntimeException: An error occurred while executing doInBackground()
at android.os.AsyncTask$3.done(AsyncTask.java:353)
at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:383)
at java.util.concurrent.FutureTask.setException(FutureTask.java:252)
at java.util.concurrent.FutureTask.run(FutureTask.java:271)
at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:245)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1162)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:636)
at java.lang.Thread.run(Thread.java:764)
Caused by: java.lang.IllegalArgumentException: sum of a week may not be negative
at org.zephyrsoft.trackworktime.model.Week.setSum(Week.java:65)
at org.zephyrsoft.trackworktime.timer.TimerManager.updateWeekSum(TimerManager.java:598)
at org.zephyrsoft.trackworktime.timer.TimerManager.createEvent(TimerManager.java:581)
at org.zephyrsoft.trackworktime.database.DAO.restoreFromReader(DAO.java:759)
at org.zephyrsoft.trackworktime.WorkTimeTrackerActivity$15.doInBackground(WorkTimeTrackerActivity.java:1036)
at org.zephyrsoft.trackworktime.WorkTimeTrackerActivity$15.doInBackground(WorkTimeTrackerActivity.java:1021)
at android.os.AsyncTask$2.call(AsyncTask.java:333)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
... 4 more
java.lang.IllegalArgumentException: sum of a week may not be negative
at org.zephyrsoft.trackworktime.model.Week.setSum(Week.java:65)
at org.zephyrsoft.trackworktime.timer.TimerManager.updateWeekSum(TimerManager.java:598)
at org.zephyrsoft.trackworktime.timer.TimerManager.createEvent(TimerManager.java:581)
at org.zephyrsoft.trackworktime.database.DAO.restoreFromReader(DAO.java:759)
at org.zephyrsoft.trackworktime.WorkTimeTrackerActivity$15.doInBackground(WorkTimeTrackerActivity.java:1036)
at org.zephyrsoft.trackworktime.WorkTimeTrackerActivity$15.doInBackground(WorkTimeTrackerActivity.java:1021)
at android.os.AsyncTask$2.call(AsyncTask.java:333)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:245)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1162)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:636)
at java.lang.Thread.run(Thread.java:764)

[mathisdt]

A week's sum is not calculated this way anymore.